Fuse.



H. H. BAKER.

FUSE.

APPLI/nmu min um. 8. 1915. RENEwED DEC. 1,1916.

1,212,603. Patented Jan. 16, 1917.

f the means for grippin HOWARD H. BAKER, or BUFFALO, NEW Yonx.

FUSE.

Specication of Letters Patent.

Patented Jan. 16, 1917.

Application led March 8, 1915, Serial No. 12,744. Renewed December 7, 1916. Serial No. 135,701.

To all 'whom z't may concern.- f

Be it known that I, HOWARD H. BAKEma citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, vhave invented new and useful Improvements in Fuses, of which the following is a specification.

This invention'relates'to a fuse which is usually placed in janelectric circuit for the purpose of preventing-injuryrto the parts which are suppliedpwith current, such fuses usually comprising a supporting body or block having terminals which are connected with the line Wires'and ka vfusible member strip or wire which is electrically connected at its opposite ends with said terminals and Vforms part ofthe electric circuit when the load is normal butk which is melted when the load rises abovethe knormal and therefore automatically interrupts the circuit.

The object of this invention is to produce a fuse for this purpose which'can be manufactured at comparatively low cost, which permits of readily renewing the fuse strip or wire when the same becomes melted or broken, which is thoroughly insulated so far as its metallic partsare concerned, and which is so designed that arcing betweenthe 5 terminals after melting of the fuse strlp or wire is eiectually prevented.

In the accompanyingjdrawmgs, Figure l yis a perspective vview ofthe body portion vor block of the fuse and the parts mounted thereon. Fig. 2 is a similar view of the supporting plate, shutter orfcover which carries the fuse strip or wire and forming an e ectrical connection of the same with the terminals of the fuse.

Fig. 3 is a vertical longitudinal section of.

the fuse embodying one form of my improvements in an assembled condition. Figs. v 4, 5 and 6 are horizontal sections taken-in n the correspondingly numbered lines in Fig. 3. Fig. 7 is a perspectivevview of the fuse. strip shown in Figs. 2 and 3. Fig. 8 is 'a' vertical longitudinal section similar to Fig.

3 but showing a modified form of some parts of the fuse. Fig. 9 is a perspectivel View of the fuse strip shown in Fig. 8.

Similar characters of reference indicate corresponding parts throughout the several views. y

Referringy to Figs. 1-7, 1 represents the bod, or block of the fuse holder which is pre erably constructed of porcelain or other vitreous and electric insulating material. At

Vfuse holder the same is provided on one or more of its sides with recesses 4, 5 in which upper and lower contact sockets of metal 6, 7 are seated. The holder body is preferably constructed of square or rectangular form 1n cross section, and as shown in Figs. 1 6, et, 5 and 6 the same is provided on two of lts diametrically opposite sides with pairs of upper and lower contact sockets 6, 7 the number of such pairs being varied depending upon'the size of the fuse and the particular purpose for which the same is intended.

The contact sockets at one end of the holder body are preferably connected with each other and also with the adjacent terminal ofthe fuse such an arrangement being indicated at the lower end of Fig. 3 relative to the lower sockets 7 and terminal 3, while the corresponding contact sockets 6 at the other end `of the holder may be electrically disconnected from each other and adapted to be individually connected with or disconnected from a Contact plate S arranged at the innery end' of the adjacent terminal 2. Such a construction is shown at the upper end of Fig. 3 in which the upper sockets 6, 6 are not electrically connected with each other and they are also separated individually by intervening gaps, recessesor spaces 9 from a contact plate 8 which is arranged at the inner end of the upper terminal 2.

The contact sockets 6, 7, plate 8 and the terminals are preferably secured in the body or block of the fuseby placing these contacts, plate and terminals within the plastic mass of the body while the latter is being molded and retained therein while the body is being vitriiied or hardened. By this means the terminals and contact members are mounted on the body without the use of any screws, solder or other connecting means which not only reduces the cost of manufacture but also avoids the projection of any metallic parts on the exterior of the fuse body as well as disconnection of these parts. The openings of the `several sockets and also the recesses or gaps between the upper sockets and the contact plate 8 open outwardly to the surface of the insulating sup t porting body 1 to permit of parts being inserted thereinto and also removed therefrom.

\ Means are provided for connecting the two,4 sockets on each side ofthe fuse body by means of a fusible member having preferably the form of a strip or iat wire and also connecting one of the individual sockets G with the contact plate S of the adjacent terblows out, thereby enabling the electric circuit to be restored without interrupting the same an undue length of time. The preferred means for this purpose which aie shown in the drawings compi'ise a plurality of supporting plates or covers of insulating material each of which is normally arranged witliiii a marginal rim 11 on the body and extends over and completely covers one of the sides of the body containing ay companion set of contact socket-s and the adjacent end of the contact plate 8 of the upper terminal. On the inner or rear side of this supporting plate or cover two pairs of jaws 1Q, 13 of metal are mounted, one pair at the upper end and another at the lower end thereof which jaws are adapted to receive between them the opposite ends of a fuse strip or wire and also to engage with a wet ging action in the contact sockets G, 7 so as to forma perfect electrical connection between the latter. Each of these jaws is preferably provided with a base flange 11i whereby the same may be secured to the inner side of the supporting plate by rivets 15 or the like.

he wedging action of the jaws of each pair with the respective socket into which the same is pushed is preferably effected by rounding or tapering the free ends of the jaws of each pair, as shown in Fig. 3, so that upon entering the respective socket these jaws are pressed toward each other.

The fusible member, strip or wire 1G which is used in this fuse is preferably constructed in the shape of the letter U and comprises a longitudinal central portion or body 17 and two laterally projecting tabs or lips 18, 1f) arranged at opposite ends of rthis body and extending inthe saine direction. In mounting the fuse strip in the fuse holder the tabsY of the fuse strip are first placed between the respective pairs of jaws and then the latter are pushed into the companion pair of sockets 6, 7 on the holder body, whereby the jaws of each pair are pressed toward each other by the wedging action of the same against the bore of the respective socket and the adjacent tab of the fuse strip is gripped between the companion jaws, thereby insuring a reliable electrical connection between the two sockets on the same side of the fuse and also retaining the parts in place relatively to each other without requiring any special means for this purpose. ln order to.

still further increase the electrical connection between the jaws and the fuse strip the two tabs of the latter are corrugated transversely, as shown at 2O in Fig. .7 and the opposing faces of the two jaws or each pair are correspondingly corrugated, as shown at 21, for receiving the corrugated portions of the tabs between the same. By this means, a firm interlock between the fuse strip and the clamping jaws is produced which insures an extended electrical contact between the same.

In order to permit the fuse strip to bc thus assembled with the body of the holder the latter is provided on each of its sides containing a pair of sockets with a longitudinal fuseway or groove 22 which is arranged at one side or out of line with the respective sockets and connects the corresponding lateral sides of these sockets, as shown in Figs. 1 and 11e-6. As the pairs of jaws carrying the tabs ofthe fuse strip enter the sockets the body or central part of the fuse strip enters the'fuseway and thereby enables the cover carrying `these parts to be moved close to the respective side of the body of the fuse holder and come within the marginal rim 11.

For the purpose of completing the circuit between one terminal and another a removable key or plug 23 is provided which is adapted to be inserted through corresponding openings 24, 25 in the upper part of the cover and the Harige of the adj acont jaw and into the adjacent recess 4 so as to engage on its underside with the top of the adjacent socket G and on its upper side with the underside of the adjacent part of the contact plate 8, as shown in Fig. 3. lVhen this key is thus inserted an electrical path is completed between the terminals. AIf the fuse strip which is in operation should be blown or burned out it is only necessary to withdraw the key from the respective recess with which the saine engages and introduce the same into the other recess on the opposite side of the body so as to electrically connect the upper socket of the other line with the contact plate 8 of the upper terminal, thereby restoring the circuit without undue interruption of the same. f In the meantime the fuse wire or strip which has been just melted or blown out may be again replaced so that the same is held in readiness for the next emergency.

Inasmuch as the fuse strip presents the flat sides of its body or central part to the opposite flat sides of the fuseway between the upper and lower sockets the Haine produced during the melting of the fuse strip extends or flashes from the opposite fiat sides of the fuse lstrip toward the companion flat sides of thefuseway instead of in a forward direction toward the outlet of the fuseway. The pressure of the gases during such blowing out of a fuse strip therefore does not operate to push the cover off from the body of the holder. Any gases which develop in the fuse way during blowing out of the fuse strip are conducted to the outer atmosphere through a vent opening 26 arranged in the central part of the covei` which is on one side of the front end of the fuseway. These gases therefore are obliged to make a sharp turn in passing from the fuseway through the vent opening to the atmosphere, whereby any flame is prevented from shooting directly from the melting fuse to the outer atmosphere but instead this flame is conned within the fuseway and only the hot gases under pressure are permitted to escape through the vent opening, thereby avoiding setting fire to anything in the immediate vicinity of the fuse when the same blows out under overload.

The issuing of a flame from the vent opening is further prevented by placing a guard 27 on the outer side of the cover over this opening which guard not only further diverts the course of the escaping gases but also performs the function of a handle whereby the cover may be applied to or removed from the body of the fuse holder. This handle may be formed in any suitable manner but preferably by stamping the same out of the same material which forms the cover, as shown in the drawings. Furthermore, by arranging each fuseway in the insulating body of the holder on one side of the companion sockets the possibility of producing an electric arc between these sockets is avoided, thereby eliminating the danger of fire in the vicinity of the fuse as would be liable to occur if such arcing were possible.

In the modified construction of my im? proved fuse shown in Figs. 8 and 9, the body 28 of the holder is provided with only one pair of sockets 29, 30 and these are both connected directly with the terminals 31, 32, thereby avoiding the use of a key as above described, and the fuse strip or wire is provided at opposite ends of its body 33 with ilat tabs or lips 34, 35 which are adapted to be gripped between the opposing flat sid-es of the jaws 36, 37 which are mounted on the cover and engage with a wedge action in the sockets 29, 30 for producing a reliable electric connection between the fuse strip and these sockets.

If desired the body of the holder may be provided with a chamber or compartment in which spare fuse elements may be stored ready for instant use in case the fuse strip in circuit has been destroyed. As shown in Fig. 8, such a storage chamber 38 is shown in that side of the body 28 opposite the one containing the sockets 29, 30 and the reserve fuse strips 39 are confined in this chamber by a lid 40 which may be movably mounted on the body 28in any suitable manner.

This fuse as a whole is exceedingly simple in construction, it contains but few parts, the same is not liable to get out of order and owingvto the fact that most of the metallic parts are covered by insulating material the safety of the fuse is materially increased.

I claim as my invention:

l. The combination of a fuse block of insulating material, rigid sockets mounted on said block, a supporting plate of insulating material, and two pairs of jaws which are arranged on said plate and the members of each pair being adapted to engage one of said sockets and to receive one end of a fusible member between the same, the cooperating surfaces of said jaws and sockets being constructed to produce a wedging action on said jaws whereby the members of each pair are pressed toward each other and against opposite sides of the fuse between the same. f

2. The combination of a fuse block of insulating material, two rigid metal sockets arranged in said block, a supporting plate, two rigid pairs of metal clamping jaws mounted on said plate and the members of each pair being constructed to engage by a wedge action with one of said sockets, and a fusible member having a longitudinal body and laterally projecting tabs at its ends each of which is adapted to be gripped between the jaws of one of said pairs, and said block being provided with a fuseway which places corresponding lateral sides of said sockets in communication and is adapted to receive the longitudinal body of said fusible member.

3. The combination of a fuse block of insulating material, two rigid metal sockets arranged in said block, a supporting plate, and two rigid pairs of metal clamping jaws mounted on said plate and the members of each pair being constructed to engage by n a wedge action with one of said sockets and to grip between them one end of a U-shaped fuse strip and said block having a fuseway extending between said sockets and adapted to receive the central part of the U-shaped fuse strip.

4. The combination of a block of insulating material which is provided with a fuseway adapted t0 receive the central part of a U-shaped fuse strip, two metal sockets mounted on the block at opposite ends of the fuseway, two pairs of clamping jaws adapted to grip opposite ends of said fuse strip and to engage by a wedge action with said sockets, and a supporting plate on which said jaws are mounted and which is provided with a vent opening, said fuseway being arranged on one side of said sockets and said vent opening so as to produce an angular path from said fuse to the atmosphere for the escape of the gases when the fuse burns out.

5. The combination of a fuse block of insulating material, rigid sockets mounted on said block, and two pairs of rigid jaws, the members of each pair being adapted to engage one of said sockets and to receive one end of a fusible member between the same, the coperating surfaces 0f each pair of jaws and the companion socketbeing constructed to produce a wedging action on the respective jaws whereby the members of each pair are pressed toward each other and against opposite sides of the fuse between the same.

Witness my hand this 2nd day of March,

HOVARD H. BAKER. Viitnesses:

THEO. L. Pori), E. M. GRAHAM.

Copies of this patent may be abtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

